Apparatus for power-driven typewriters and similar machines

ABSTRACT

A mechanism for shifting lines and returning the carriage to its left-margin position in power-driven typewriters and similar machines having a drive motor, and including a manually controlled member for triggering both the line shifting and carriage return operations, two linkages resiliently connected to the member and each arranged for normally producing a respective one of the operations, and various blocking means for selectively blocking the operative connection between the member and either linkage when the operation produced by that linkage is not to occur; particularly for blocking the carriage return linkage when the carriage is already in its left-margin position. A link member resiliently connected by means of a spring to the other of the arm members of the pivotally mounted lever and operable to pivot a crank provided on the clutch to engage that clutch and return the carriage, and reciprocating elements provided to block either the connecting rod or the link when only a line shift or a carriage return, respectively, is desired.

United States Patent Kittel et a1. Feb. 22, 1972 [54] APPARATUS FORPOWER-DRIVEN 778,229 12/1904 Doederlein ..l97/12O X TYPEWRITERS ANDSIMILAR 2,286,318 6/1942 Sundstrand.... 197/66 MACHINES 3,200,197 8/1965Krakusky ..l97/l20 X 2,965,211 12/1960 Toggenburger ..197/66 [72]Inventors: Arthur Kittel, Wilhelmshaven; Rudi Frank, Sande; Horst Purr,Primary Examiner-Robert E. Pulfrey helmshaven, all of Germany AssistantExaminer-R. T. Rader [73] Assignee: Olympia Werke AG, Wilhelmshaven,Ger- A'mmeySpe"cer Kaye many [57] ABSTRACT [22] Filed: Apr. 23, 1970 Amechanism for shifting lines and returning the carriage to its PP 31,078left-margin position in power-driven typewriters and similar machineshaving a drive motor, and including a manually con [30] ForeignApplication Priority Dam trolled member for triggering both the lineshifting and carriage return operations, two linkages resilientlyconnected to Apr. 26, 1969 Germany UP 19 21 414.3 the member and eacharranged f normally producing a respective one of the operations, andvarious blocking means [52] [1.5. CI ..197/66, 197/120 for Selectivelyblocking h operative connection between the [51] ll. Cl. ..B41 19/70member and either linkage when the operation produced by [58] Fleld ofSearch ..197/65, 66, 1 15, 120 that linkage is notto occur; particularlyfor blocking the cap riage return linkage when the carriage is alreadyin its left- [56] l References C'ted margin position. A link memberresiliently connected by UNITED STATES PATENTS means of a spring to theother of the arm members of the pivotally mounted lever and operable topivot a crank pro- 1 BI'PWI'I X Vided on the clutch to engage thatclutch and return the car- 3,263,793 8/1966 Blngndlel J -197/120 riage,and reciprocating elements provided to block either the 2,168,448 8/1939l 197/120 X connecting rod or the link when only a line shift or acarriage Pitman return respectively, is desired, 2,333,566 11/1943Helmond.... .....l97/66 2,541,295 2/1951 Sagner 197/66 6 Claims, 6Drawing Figures Lil 38 36 340 35 26 Alb T I 21 m 4 l8 4";

, 1 \f: A d V-/ 8 w r f PATENTEDFEH 22 I972 SHEET 1 UP 4 II NENTORSArthur Kittel Rudi Frank Horst Purr BY JIM 4,

ATTOR NEYS.

PATENTEDFEB 22 I972 SHiET 2 BF 4 Arthur Kiriel Rudi Frank Horst PurrATTORNEYS.

PAIENTEDrzazz 1912 SHEET []F 4 INVENTORS.

mmnfl K m m W i mm HUO RH ATTORNEYS.

APPARATUS FOR POWER-DRIVEN TYPEWRITERS AND SIMILAR MACHINES BACKGROUNDOF THE INVENTION The present invention relates to a device for shiftinglines and returning a carriage to the left-margin position inpowerdriven typewriters and similar machines by means of a clutch whichcan be engaged by the margin set abutment of the machine to connect thepower drive with a mechanism for returning the carriage.

Such devices are known per se. The return of the carriage to itsleft-margin position is usually accomplished after a line shift; or theline shift is accomplished without carriage return.

Most of these devices are of the type where the carriage return,together with the line shift, is effected by means of pulley cables.

A device has also become known which is provided with two independentlyoperating gear mechanisms; one each for driving the carriage and forshifting a line.

The drive mechanism for the line shift has a single-revolution clutchwith two associated curved discs. The curved disc serving for the lineshift is connected with the power drive for the duration of onerevolution. The curved disc provided for the movement of the carriage,however, acts through a lever arrangement on a further clutch, whichconnects the power drive with a mechanism for returning the carriage.The drive of the two independently operating gears is accomplishedeither directly or indirectly through belt drivesby the drive motor;which is simultaneously switched on when either the line shift orcarriage return keys are actuated, and which is switched off aftercompletion of the respective function.

When the carriage is returned to the left-margin position, it is moved,in the usual manner, a little past the set margin into the so-calledovershoot position, and takes up its final position immediatelythereafter.

During this movement, the pawls ofa detent unit used to set the marginsare out-of engagement with the conventional toothed rod, and are held inthe raised position until the carriage has come to rest at the setmargin. Since the pawl is out of engagement with the toothed rod, aso-called margin displacement can not be avoided. This margindisplacement comes about due to the fact that the pawl, which has beenlifted out of the toothed rod, engages too early into a gap between theteeth and, thus, the carriage does not reach the correct marginposition.

A further drawback of this prior art device is that with successive lineshifting when the carriage is in the left-margin position, the carriageis moved past the margin position into the overshoot position and backagain each time, which causes very annoying switching noises.

A device has become known which seeks to prevent the margin displacementby associating a longitudinally displaceable blocking latch with thegear assembly for releasing the pawl from the toothed rod. This blockinglatch catches in the toothed rod shortly before the carriage has reachedthe margin position.

When repeated line switching in the left-margin position is performed,the pawl is lifted from the toothed rod as usual, so that the carriagewith its longitudinally movable blocking latch is moved each time beyondthe margin position into the overshoot position and back again.

The addition of the longitudinally displaceable blocking latch thusfixes-the left-margin position of the carriage in such a manner that itis stopped in the correct position and the pawl is able to fall into thetoothed rod in this position.

The annoying switching noises repeated during the line switches are notremoved by this device, however. Moreover, this arrangement is highlysubject to malfunctions and, thus, not dependable.

The carriage return with the preceding line shift is accomplished inthese embodiments by actuating the conventional carriage return key. Acontinuous line switching after completed carriage return by means ofthis key is not provided.

For line shifting without carriage return in the left-margin position aspecial line switching key disposed on the keyboard is required.

These known embodiments are relatively complicated and, thus,unnecessarily expensive, so that the total cost of the typewriter isunduly increased.

SUMMARY OF THE INVENTION It is, therefore, an object of the presentinvention to provide a device which eliminates the above-mentioneddisadvantages and similar drawbacks, and which is particularlydistinguished by its simplicity and dependability.

This is accomplished according to the present invention by providing aU-shaped bar with a pair of arms for actuating the line shift and thecarriage return. This bar is pivotal about a shaft and is associatedwith a longitudinally movable resiliently mounted connecting rod whichis joined to an inter mediate lever, and with a link which is held inoperative connection with an arm of the U-shaped bar by means ofatension spring; the link cooperating with a clutch coupling crank forconnecting the carriage return mechanism with the drive mo- I01. Thepresent invention is particularly distinguished from known devices inthat the carriage return mechanism is switched off during repeated lineshifts without carriage return when the carriage is in the left-marginposition and, thus, in addition to the resulting reduced wear on theswitching gears, the annoying and interfering switching noises areeliminated.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a front elevation view ofthe apparatus according to the present invention in its starting, orrest position.

FIG. 2 shows a top plan view of the apparatus of FIG. 1.

FIG. 3a shows a front elevation view of the apparatus according to thepresent invention in its operative position.

FIG. 3b is a front elevation view showing a detail of FIG. 311.

FIG. 4a is a front elevation view of the apparatus according to thepresent invention with the carriage at the left-margin and in theblocked position with the clutch disengaged.

FIG. 4b is a front elevation view similar to FIG. 3b showing a detail ofFIG. 4a.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIGS. 1 and2, element 1 is a shaft journaled in the rear wall of the housing member2 and in a parallel intermediate wall 3 (see FIG. 2). A U-shaped lever 4is mounted on shaft 1 so as to define a fulcrum 4'. On one end of thefulcrum 4, lever 4 is provided with an upwardly extending arm 5, whileon the other end it is provided with a downwardly directed arm 6. Arm 6is further provided with a rectangular bent portion 8 provided with aslot 7 which is open at end 7' (FIG. 2). A connecting rod 9 isassociated with the upwardly extending arm 5, and is pivotally connectedin a known manner with a bellcrank lever 11 which is mounted on a shaft10 and acts on a known line shift mechanism (not shown). The connectingrod 9 is provided at its free end with a longitudinally extending, openslot 12 into which arm 5 of lever 4 engages and is held in operativeconnection with connecting rod 9 by a tension spring 13 fastened toconnecting rod 9. In addition, the connecting rod 9 is provided with anangularly bent flap 14 which may come into operative engagement with areciprocative blocking member 15, depending on the function to beperformed. Member 15 is reciprocated by a known mechanism.

A forked link 16 engages in open slot 7 of the rectangularly bentportion 8 of arm 6, and is held there by a tension spring 17 fastened tothe extension 6a of arm 6. Spring 17 is strong enough to move link 16 inunison with arm 6, if link 16 is not blocked. The other free end 16b oflink 16 is provided with a longitudinally extending, open-ended slot 18which engages a clutch crank 21. Crank 21 is pivotally mounted at 19 andis under the influence of a suitable tension spring 20. The link 16 isfurther provided with a protrusion which may come into operativeconnection with a reciprocative blocking member 22. Member 22, likemember 15, is reciprocated by a known mechanism (not shown). Two cams21a, 21b are disposed on clutch crank 21, and link 16 slides betweenthese two cams. The clutch crank 21 is provided with a parallelextending protrusion 21c which engages in a recess portion 23b of onemember 230 ofa jaw clutch 23. Clutch member 2311 is longitudinallydisplaceable on, and free to turn on, shaft 24 ofa suitable, known drivemotor 25. The other clutch member 23' is mounted for rotation with shaft24. A pinion 230 is provided between recess 23b and the main body ofmember 23a, and is permanently engaged with a freely rotatable crownwheel 27 mounted on a shaft 26 which is perpendicularly arranged withrespect shaft 24. Shaft 26 is mounted in a known manner in a bearingbracket 28 mounted on the intermediate wall 3 (the mounting is notshown). The crown wheel 27 is in friction contact with a frictionoverload clutch 30, formed of a spring disc 29 in frictional connectionwith crown wheel 27. At the upper end of shaft26, there is a pinion 31which cooperates with the rack 32 mounted on the carriage (not shown).On the socalled toothed margin set rod 33, which is part of thecarriage, there is disposed the displaceable and adjustable left-marginsetter 34, provided with an abutment tongue 34a. Below the toothedmargin set rod 33, a shaft 35 is mounted in the frame of the machine(not shown), on which the known switching bridge 36 is mounted. Bridge36 is held in position by a tension spring 37 and is provided with aprotrusion 38 and a trip dog 39.

A switching lever 41 is mounted on a bolt 40 disposed in the rear wall 2ofthe machine housing. This switching lever 41 is provided with an arm41a and an upwardly directed protrusion 41b. In the rest, or starting,position the switching lever 41, together with protrusion 41b, are underthe influence of a torsion spring 42 and in contact with the trip dog 39(see FIGS. 1, 3a and 3b).

A holding rod 43 is disposed above the clutch crank 21, which rod 43 isarranged parallel to the plunger 16 and is provided with two downwardlydirected steps 43a, 43b (FIGS. 3b and 4b).

The apparatus according to the present invention operates as follows:

Depressing the carriage return key, which is known in the art and,therefore, not illustrated, causes the lever 4 to be pivotedcounterclockwise by a known drive mechanism (not shown). The connectingrod 9 which is pivotally connected to lever 11, is acted on by arm andperforms a pulling movement. The lever 11, which is operable to effect aline shift in a known manner, then performs a clockwise rotatingmovement and causes a line shift. At the same time, the plunger 16 ismoved toward the right in FIG. 1 by the force ofspring 17, and causesthe clutch crank 21 to perform a counterclockwise rotary movement aroundpivot 19. With this rotary movement, clutch member 23a, is brought intoengagement with the continuously rotating member 23' of clutch 23 (FIG.3a). Simultaneously with the displacement of plunger 16 described above,the free end of crank 21 is pulled slightly upwardly under the influenceof tension spring 20, and first comes to rest in the step 43a of theholding rod 43 (FIG. 3b). The connection of the two clutch members 23and 230 causes a rotary movement to be imparted through pinion 23c tocrown wheel 27, so that the pinion 31 is disposed on shaft 26 causes thecarriage to return into the left-margin position by means of rack 32.

In the starting, or rest, position, the switching bridge 36 is incontact with the protrusion 41b of switching lever 41 through its tripdog 39 (FIG. 1).

With the arrival of the abutment tongue 34a, disposed on the margin setmember 34, at the protrusion 38 of switching bridge 36, during thecarriage return movement to the leftmargin position, the switching lever41 is pivoted slightly counterclockwise against the force of the torsionspring 42 the exact amount depending on the known overshoot. Arm 41apresses crank 21 out of step 43a of holding rod 43 during this pivotingmovement. The crank 21 then goes to step 43b under the influence ofspring 20, and clutch member 2311 is resultingly brought out ofengagement with the continuously rotating clutch member 23' to interruptthe power drive.

Tension spring 36a provided in switching bridge 36 serves the purpose ofmarking the margin position when the carriage is manually moved to theleft-margin position and, on the other hand, of absorbing the kineticenergy of the carriage in a power-driven carriage return by motor 25after clutch 23 has been disengaged.

At the moment of release of the carriage return key, when the line shifthas already been accomplished, lever 4, the link 16 and connecting rod 9all take up their starting positions; although the carriage returnitself is still going on. To protect the drive motor'25 from possibleoverloads, particularly when the carriage starts moving, the carriagereturn mechanism consisting of crown wheel 27 and pinion 31 is providedwith overload clutch 29, 30, which will protect the drive motor 25against any possibly occurring overloads.

Upon the actuation of the carriage return keyas already describedtheline shift is simultaneously actuated as well as the carriage return.Before the carriage reaches the left-margin position, however, the lineshift has already been completed.

Quite often, it is necessary that one or a plurality of successive lineshifts must be made after the carriage has taken up its left-marginposition. This can be done with the carriage return key, as well as withthe known line shift key.

For this purpose, the carriage return key can be pressed against aresistance from the normal depressed level to a further depressed level.After the carriage has completed its return into the left-marginposition, the trip dog 39 of the switching bridge 36 is in contact withthe protrusion 41b of the switching lever 41, such that the bent portion41c of its arm 41a comes to lie in front of crank 21 and, blocks link 16(FIGS. 4a,4b).

Thus, when the carriage return key is depressed further downward againsta resisting element (not shown), it effects one or a plurality ofsuccessive line shifts; the carriage return being prevented by theblocking of link 16. The pivot path of arm 6 only causes a stretching ofthe tension spring 17 connecting link 16 and arm 60.

If a line shift is to be performed without a carriage return in anydesired position of the carriage, it is done by actuating the known lineshift key. With the known drive mechanism, the lever 4 is pivotedcounterclockwise.

Simultaneously with the actuation of the line shift key, the blockingmember 22 is moved by a known mechanism to enter the path of movement ofprotrusion 16c oflink 16, so that link 16 is unable to perform alongitudinal movement to the right in FIG. 4a. This has the result thatagain the pivoting movement of arm 6 only causes a stretching of thetension spring 17 while link 16 remains in the block starting position.

If a carriage return is to be made to the left-m argin position withouta line shift, it is done by a special key (not shown), upon whoseactuation the blocking member 15 is moved by a known mechanism isbrought in front of flap 14 of connecting rod 9.

During the pivoting movement of arm 5, which movement is transmitted toit by the drive mechanism, the connecting rod 9 is held in its restposition by blocking member 15, while arm 5 slides in slot 12 ofconnecting rod 9 against the force of tension spring 13. The pivot pathof arm 5 then merely stretches the spring 13.

Upon the occasion of the movement of arm 5, arm 6 positively actuateslink 16 and causes the carriage to be returned, while, as intended, aline shift is omitted. With the release of the special key, the blockingmember 15 again moves out of the path of movement of the flap 14 ofconnecting rod 9.

It will be understood that the above description of the presentinvention is susceptible to various modifications, changes andadaptations, and the same are intended to be comprehended within themeaning and range of equivalents of the appended claims.

We claim:

1. Apparatus for shifting lines and returning the carriage to itsleft-margin position in power-driven typewriters and similar machineshaving a drive motor, comprising, in combination:

a. a clutch having a crank and movable between a position engaged withthe drive motor and a position disengaged from the drive motor;

b. a lever mounted to be pivoted and having two arm members;

c. a pivotally mounted crank member operable to cause a line shift;

d. a connecting member connected to said pivotally mounted crank memberand to one of said arm members of said lever; and

e. a link member resiliently connected to the other of said arm membersof said lever and operably connected to said crank of said clutch tourge said clutch into its engaged position when said lever is pivoted,

the other of said arm members having a main body and a portion at rightangles to said main body, which portion has an open slot therein inwhich said link member is resiliently mounted, and further including atension spring connected to said portion of said other arm member and tosaid link to provide the resilient connection permitting the link memberto be moved longitudinally when said lever is pivoted.

2. Apparatus as defined in claim 1, wherein said connecting memberdefines an open slot in which said one of said arm members of said leveris mounted, and further including a tension spring connected betweensaid connecting member and said one of said arm members to provide aresilient, operative connection between said connecting member and saidone of said arm members.

3. Apparatus as defined in claim 3, further including a first blockingmember which can be moved into engagement with said link member toretain said link member when only a line shift is desired, and a secondblocking member movable to engage said connecting member and to retainsaid connecting member when only a carriage return is desired.

4. Apparatus as defined in claim 3, further including a switching leverpivotally mounted and biased by a torsion spring, and having an armmember and a protrusion, and a switching bridge arranged to engage saidprotrusion when the carriage is in the left-margin position and pivotsaid switching lever into a blocking relationship with respect to saidlink member.

5. Apparatus as defined in claim 4, wherein said clutch is a jaw clutchhaving a driving member and a driven member carrying a pinion, andfurther including a crown wheel in driving connection with both thecarriage and said pinion.

6. Apparatus as defined in claim 5, further including a shaft on whichsaid crown wheel is mounted to be freely rotatable, and a frictionclutch in the form of a spring disc mounted on said shaft in drivingengagement with said crown wheel so as to frictionally connect saidcrown wheel with said shaft.

1. Apparatus for shifting lines and returning the carriage to itsleft-margin position in power-driven typewriters and similar machineshaving a drive motor, comprising, in combination: a. a clutch having acrank and movable between a position engaged with the drive motor and aposition disengaged from the drive motor; b. a lever mounted to bepivoted and having two arm members; c. a pivotally mounted crank memberoperable to cause a line shift; d. a connecting member connected to saidpivotally mounted crank member and to one of said arm members of saidlever; and e. a link member resiliently connected to the other of saidarm members of said lever and operably connected to said crank of saidclutch to urge said clutch into its engaged position when said lever ispivoted, the other of said arm members having a main body and a portionat right angles to said main body, which portion has an open slottherein in which said link member is resiliently mounted, and furtherincluding a tension spring connected to said portion of said other armmember and to said link to provide the resilient connection permittingthe link member to be moved longitudinally when said lever is pivoted.2. Apparatus as defined in claim 1, wherein said connecting memberdefines an open slot in which said one of said arm members of said leveris mounted, and further including a tension spring connected betweensaid connecting member and said one of said arm members to provide aresIlient, operative connection between said connecting member and saidone of said arm members.
 3. Apparatus as defined in claim 3, furtherincluding a first blocking member which can be moved into engagementwith said link member to retain said link member when only a line shiftis desired, and a second blocking member movable to engage saidconnecting member and to retain said connecting member when only acarriage return is desired.
 4. Apparatus as defined in claim 3, furtherincluding a switching lever pivotally mounted and biased by a torsionspring, and having an arm member and a protrusion, and a switchingbridge arranged to engage said protrusion when the carriage is in theleft-margin position and pivot said switching lever into a blockingrelationship with respect to said link member.
 5. Apparatus as definedin claim 4, wherein said clutch is a jaw clutch having a driving memberand a driven member carrying a pinion, and further including a crownwheel in driving connection with both the carriage and said pinion. 6.Apparatus as defined in claim 5, further including a shaft on which saidcrown wheel is mounted to be freely rotatable, and a friction clutch inthe form of a spring disc mounted on said shaft in driving engagementwith said crown wheel so as to frictionally connect said crown wheelwith said shaft.